Method of setting the twist of rayon yarn



Patented Aug. 11, 1936 UNITED STATES mrrnon or snrrrmo 'nm TWIST 0F anonYARN r John Marshall Hood, Pawtucket, n. I.

' No Drawing. Application April 11, 1932,

- Serial No. 604,647

8 Claims.

This invention relates to improvements in the methods of setting thetwistof rayon yarn, whereby it becomes possible to spin the yarndirectly onto weaving or shuttle bobbins, without the necessity ofrewinding it to other carriers as a result of the yarn becoming soft orloose on the bobbins, due to a twist-setting operation, therebyeliminating time, expensive machinery and a high labor cost. Yarnshaving the twist set by my methods will not have to be kept in aconditioning atmosphere. It also applies to the setting of the twist ofrayon yarn spun onto intermediate bobbins, or carriers, from which itmust later be rewound onto weaving or shuttle bobbins, or toothercarriers; such rewinding not being necessary because of faultytwist-setting, but simply to get the yarn onto a more convenientcarrier. It also applies to the setting of the twist of cotton, wool,real silk, Celanese", and other natural or artificial fibres spundirectly onto weaving or shuttle bobbins, or onto intermediate bobbinsfor a'later rewind onto suitable caniers; it also applies to thepreparation of the yarn with the materials used previous to spinning andthen spinning directly onto weaving or shuttle bobbins, or

onto intermediate bobbins, the yarn, after spinning, requiring noafter-treatment to set the twist, when properly'prepared, beforespinning.

Yarn properly treated by my process will be firmly and tightly wound onthe bobbin, or other carrier to which it has been twisted and will notrequire a rewind because it is not firm or tight. Moreover, said yarnwill not soften, or become loose during the storage. Any rewindingrequired will be for the purpose of transferring the yarn to a moreconvenient form of carrier and not because of the yarn becoming loose,as the result,

of the twist-setting.- Another feature of my improvement. is that thetwist-setting materials can be recovered and re-used. 4

The usual method in spinning rayon yarn, at the present time, consistsin preparing it for spinning by employing a preliminary treatment, .assizing, waxing, oiling, or other treatment, then passing it through thespinning process and winding it onto bobbins, not weaving or shuttlebobbins. The yarn on the bobbin is now too lively, due to kinks, tobehandled and the'twist must be set before the yarn can be furtherprocessed. This is accomplished in several ways; by means of water orwater solutions of gums, starches, dextrines, oils, waxes, by steaming,or by a combination of materials. The treated yarn is then dried, ifneed be, and then wound onto weaving or shuttle bobbins. This maynecessitate winding REISSUED from the spinning room bobbins to spoolsonspooling machines, and then winding from spools to the weaving orshuttle bobbins on expensive winding machines. The cost of twist-settingand re-' winding is high and my process is designed to 5 eliminate muchof the expense.

When rayon yarn is spun directly from a spinning frame onto weaving orshuttle bobbins and the twist set by the methods in use at the presenttime, such as immersing the yarn in water, or 1 in water solutions ofgums, oils, waxes, starches, dextrines, etc., or steamed, the yarn,especially'- in storage, may swell and soften so that in some cases thebobbin can be pulled away from the yarn. Such bobbins cannot be used forweaving. 15 Claims are made that the yarn does not swell, but that thebobbin dries out. I claim, for my improved process, that it will remedythe trouble, whatever the cause. If due to the bobbin drying, mytreatment will overcome the difiiculty for, if a properly conditionedbobbin is used at the start, it becomes coated with a protecting layerof wax, oil, or rosin, or other binder, and would neither dry out norswell appreciably. Moreover, my treatment need not appreciably alter thenatural moisture content of any yarn to which it may be applied, andtherefore, the tendency to swell in storage, due to water take-up, wouldbe minimized. If the fabric to be treated is a crepe consisting of ahighly twisted filling (for instance 30 50-55 turns per inch per denier40 filament rayon) and, the warp ordinary untwisted rayon, and the warpis sized with a mixture similar to I that used in setting the twist, theuse of expensive humidifying apparatus in weave rooms can be 35eliminated, then the bobbins and yarn will not be exposed to changes inatmospheric conditions to produce swelling or drying out. My improve-.ment, therefore, consists in employing a binder for the yarn that doesnot cause it to swell, or soften, and does not permit the bobbin to dryout or shrink, or become damp with humidity changes.

The main object of ;my process is to spin directly onto weaving orshuttle bobbins, but protection is also claimed for twist-setting withthe same solutions, if intermediate bobbins are used; the yarn beingrewound onto the shuttle bobbins, unless wanted for warp yarn, when itwould be made into warp. The twist may beset in two different ways,according to ones choice:-

- a.. Spin the yarn onto weaving or shuttle bobbins, or other carriersand set the twist after the spinning operation, by means of chemicals tobe hereinafter mentioned. 55

' b. Prepare the yarn with chemicals to be hereinaiter mentioned. Next,spin the yarn onto weaving bobbins, which are then ready for weaving,without after-treatment. The yarn may also to be heated, it is advisablenot to use it, until cool and the chemicals used have had time to set.

The chemicals, which I use to set the twist, I call binders and arewaxes, as for example, Japan wax, bees wax, carnauba wax, oils, rosin,resins, stearic acid, or any other similar substances or mixtures ofsubstances capable of setting the twist.

By the term oils is meant the common oils used in textile processingthat are well known to textile technologists. These include:-

1. Animal oils, for example, lard, neatsfoot, red oil (oleic acid),tallow.

2. Vegetable oils, for example, olive, cottonseed, castor, rape-seed,peanut.

3. Mineral oils of the grades sold for textile finishing operations.

For the most economical working of the improvement, the materials usedfor twist-setting should be recovered from the woven cloth for re-useand, therefore, should be soluble in a nonaqueous solvent, althoughwater may be present, such as carbon tetrachloride (CCh),trichlorethylene (CzHCh), alcohol, gasoline, solvent naphtha, xylene, orany other suitable similar solvent now known.

The binders may be applied in one of several ways to the yarn.

First-They may be raised to their melting point and applied to the yarn,after spinning. Thus, using Japan wax, as a binder, it is melted and asmall amount applied to the outside of each wound bobbin, either byspraying or brushing. The bobbins are then placed in a chamber heated tothe melting point of the wax and the wax allowed to penetrate the yarn.The bobbins, after cooling, are ready for use. Another way is to placethe wound bobbins in a warm (melted) binder and centrifuge out theexcess in -a centrifuge heated to the melting point of the binder.

Second.The rayon skeins can be impregnated with the binder for instance,by means of a heated centrifuge, so that the yarn, after spin- ,ning toweaving, or shuttle bobbins, will have the twist set withoutafter-treatment. Impregnating the yarn in skein form would be ofinterest to the rayon manufacturers, as they could sell their rayon,ready for twisting directly to weaving or shuttle bobbins and inaddition, by proper treatment, the same yarn could be used for warp yarnwithout additional sizing. After weaving the cloth, the binders could,for economical working, be recovered for re-use by means .of volatilesolvents.

' Third.The yarn couldalso be impregnated with hot wax on perforatedpackages, or individual threads could be sized with hot binders bydrawing through the melted binder.

The binders can be dissolved in volatile solvents, such as are listedabove. The yarn is then impregnated with the solution, the excess liquorremoved and the yarn dried by evaporation of the solvent, the solventbeing recovered for re-use by condensation. Yarn may be prepared, beforespinning, with the binder solvent solution and the twisted yarn takenfrom the spinning frame with the twist set, or the yarn before treatmentwith the solutions can be spun and the twist set after spinning bytreatment with the solutions.

Fourth.Rayon yarn could be treated in the skein form, so that it couldbe used for twisting and also for warping, without extra sizing.

Fifth-The yarn may be treated on perforated packages, or ordinarypackages. As stated, for economical operation, the binders and solventsshould be recovered.

For the most economical operation, the binders used should be recoveredfrom the woven cloth by means of solvent extraction and used over again.The solvents used are also recovered and re-used,

Formulas which will work for twist-setting after spinning are asfollows:

For 100 denier40 filament rayon spun 50-55 turns to the inch:--

Brush the outside of the wound bobbins with Japan wax heated just abovethe melting point,

then, keep bobbins in a warm place, heated to The folthe melting point.Cool and weave.

lowing admixture may be used. I

Japan wax 300 grams Carbon tetrachloride 300 cubic centimeters Thismixture can be used for impregnating skeins preceding the spinningoperations, and, the bobbins can then be taken from the spinning framewith the twist set.

The above formulas illustrate mixtures that are workable. I do not bindmyself to use of the above formulas only.

In the case of Celanese" yarns, a solvent must be used that isnon-injurious to the Celanese.

By variation in the quantity of the different ingredients used, asbinder mixtures, differences in stiffness, elasticity, and stickinesscan be imparted to the yarn depending upon the effects one desires toobtain. If the woven cloth is prop erly extracted with solvent, thebinders should all be removed. However, 11' traces were not removed,they would be secured out in the finishing process. The use of Japan waxand rosin is recommended. I also claim protection for the use of solventbinder, mixtures, described above, if the rayon is first passedthroughthe solution and then spun (so-called wet spinning process), with orwithout an aftertreatment.

My improvement is materially diflerent from shuttle, or weaving-bobbin,not so much because 76 the textile industry, as sizing, but astwist-setting or setting the twist.

Fourth-Mention is made that the impregnated yarn (sized), is to berewound onto a carrier. In my improvement, the yarn, is spun directlyonto a weaving or shuttle bobbin and does not require rewinding ontoanother carrier.

Therefore, the patentees could not have had in mind the use of theirsolutions as twist-setters for twisted yarn spun directly ontoweavingbobbins.

FifthF-The yarn can be prepared in skein form with the sizing mixture,but nothing is mentioned in theUnited States Patent No. 1,742,568, to

Addy, et al., about such use.

What I claim is:-

1. In a method of setting the twist of rayon, wool, real silk,"Celanese, and cotton yarnsand the recovery for re-use by means ofvolatile solvents of the materials used in setting the twist as well asthe recovery of the volatile solvents for the steps comprising twistingthe yarns Onto a suitable carrier, then setting the twist with a mixtureof oils, waxes and rosin, and recovering from the woven fabric, theoils, waxes and rosin by extraction with volatile solvents' andseparating said solvent from the twist-setting medium by distillation.

2. In a method of setting the twist of rayon, wool, real silk, Celanese,and cotton yarns, and the recovery for re-use,by means of volatilesolvents of the materials used in setting the-twist as well as therecovery of the volatile solvents comprising, pre-treating the yarn witha mixtureof ,oils, waxes, and rosin, then twisting the yarn ontosuitable carriers, and recovering from the woven fabric the oils, waxesand rosin by ex-.

. traction with volatile solvents and separating said solvents from thetwist-setting medium by.dis-

tillation. 3. In a method of setting the twist of rayon,

wool, real silk, Celanese", and cotton yarns and the recovery for,re-use by means of volatile solvents of the materials used in settingthe twist as well as the recovery of the volatile solvents,

the steps comprising twisting the yarns onto a suitable carrier, thensetting the twist with a mixture of oils, waxes, and rosin, constructinga fabric structing a fabric and extracting said-twist setand extractingfrom said fabric, the oils, waxes and rosin by'extraction with volatilesolvents.

4. In a method of setting the twist of rayon, wool, real silk, Celanese,and cotton yarns, and the recovery for re-use by means of volatile gsolvents of the materials used in setting the twist as well as therecovery of the volatile solvents comprising, pre -treating the yarnwith a mixture of oils, waxes, rosin, then twistingthe yarn ontosuitable carriers, constructing a fabric and extracting from said fabricthe oils. waxes and rosin by extraction with volatile solvents.

5. In a method of setting the twist of rayon, wool, real silk, Celanese,and cotton yarns and the recovery for re-use by means of volatilesolvents of the materials used in setting the twist as well asthe-recovery of the volatile solvents, the steps comprising twistingtheyarns onto a suitable carrier, then setting the twist with a twistsetting medium soluble in volatile 20 solvents, constructing a fabricand extracting said twist setting medium from the fabric by extractionwith volatile solvents. v

6. In a method of setting the twist of rayon, wool, real silk,Celanese", and cotton yarns and 25 the recovery for re-use by means ofvolatile solvents of the materials used in setting the twist as well asthe recovery of the volatile solvents, the steps comprising twisting theyarns onto a suitable carrier, then setting the twist with a 80 twistsetting medium soluble in volatile solvents, constructing a fabric andextracting said twist setting medium from, the fabric by extraction withvolatile solvents and separating said solvents from' the twist settingmedium by distillation.

7. In a method of setting the twist of rayon, wool, real silk, Celanese,and cotton yarns, and the recovery for reuse by means of volatilesolvents or the materials used in setting the twist as well as therecovery of the volatile solvents comprising pre-treating the yarn witha twist setting medium soluble in volatile solvents, then wtwisting the.yarn onto suitable carriers, con- '45 ting medium from the fabric byextraction with volatile solvents- 8. In a method of setting the twistof rayon, wool, real silk, Celanese, and cotton yarns, and the recoveryfor re-use by means of volatile solvents of the materials used insetting the twist as well as the recovery of the volatile solventscomprising pre-treating the yarn with a twist setting medium soluble involatile solvents, then twisting the yarn onto suitable carriers,constructing afabric and-extracting said twist setting medium from thefabric by extraction, with volatile solvents and separating saidsolvents from the twist'setting medium by distillation.

JOHN MARSHALL HOOD. 60

